Sensor

• US 6,083,366 A
• Filed: 10/17/1997
• Issued: 07/04/2000
• Est. Priority Date: 04/19/1995
• Status: Expired due to Term

• Current Assignee: Microarray Limited
• Original Assignee: Manchester Metropolitan University
• Inventors: Higson, Seamus Patrick John
• Primary Examiner(s): Tung, T.
• Assistant Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US08/945,049
• Time in Patent Office: 991 Days
• Field of Search: 204/403, 204/400, 204/406, 435/817, 205/777.5, 205/775, 427/2.11, 427/2.12, 427/2.13, 427/58
• US Class Current: 205/122
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001

Abstract

There is disclosed a sensor for an analyte comprising a working electrode assembly, itself comprising a micro-electrode array in which each micro-electrode is coated with a layer of redox state dependent conducting organic polymer, a counter electrode; a conductive medium containment into which the electrodes are disposed and a material for analysis may be introduced; means for applying an alternating electric polarizing potential across the electrodes; and means for detecting a variation in a conductimetric property across the {working electrode→counter electrode} plane in the presence of the analyte.

Claims

1. A sensor for an analyte comprising:

a working electrode comprising a conductive electrode having an insulating layer thereon, said insulating layer having a plurality of micropores therethrough, and a conducting organic polymer deposited in said micropores, said polymer in said micropores being electrically interconnected by said conductive electrode to form a microelectrode array;

a counter electrode;

a conductive medium containment into which the electrodes are disposed and a material for analysis may be introduced;

means for applying an alternating electric polarizing potential across the electrodes; and

means for detecting a variation in a conductimetric property across a working electrode-counterelectrode plane in the presence of the analyte.

2. A sensor according to claim 1 in which the conductive medium containment comprises a conducting solution.

3. A sensor according to claim 1 or claim 2 in which the conductimetric property detected is the impedance across the {working electrode→

counter electrode} plane.

4. A sensor according claim 1 in which the variation in the conductimetric property is detected as a function of the applied frequency.

5. A sensor according claim 1 in which the variation in the conductimetric property is detected at a single applied frequency.

6. A sensor according claim 1 in which the working electrode is fabricated by coating a planar electrode with an insulating polymer, sonically ablating the insulating polymer coating to produce a plurality of micro-pores, and depositing redox state dependent organic polymer into said micro-pores.

7. A sensor according to claim 6 in which the conducting organic polymer is deposited electrochemically, by chemical vapour deposition or by photopolymerization.

8. A sensor according claim 6 in which an enzyme is entrapped within the conducting organic polymer matrices.

9. A sensor according to claim 8 in which the enzyme is glucose oxidase, alcohol oxidase or alcohol dehydrogenase.

10. A sensor according to any of claims 6 to 9 in which the insulating polymer is polydiaminobenzenedihydrochloride, Teflon, PVC or polyethylvinylbenzene.

11. A method of fabricating a working electrode assembly comprising coating a planar electrode with an insulating polymer, sonically ablating the insulating polymer coating to produce a plurality of micro-pores, and depositing redox state dependent conducting organic polymer into said micro-pores.

12. A method according to claim 11 in which the organic polymer is deposited electrochemically, by chemical vapour deposition or by photopolymerization.

13. A method according to claim 11 or claim 12 in which an enzyme is entrapped within the organic polymer matrices.